The midnight sun months, especially June and July, bring sunny days, sometimes punctuated by afternoon cloudbursts. In the winter it gets so cold (-30°F or below) that a glass of boiling water flung out a window will reach the ground as particles of ice.
Many attractions shut down in mid-September. A trip in May avoids the rush, but it's been known to snow in Fairbanks in spring. Late August brings fall colors, ripening berries, active wildlife, and the start of northern-lights season. Winter sports enthusiasts should come in March, when the dark days of winter are over, snow blankets the ground, and there's lots of sun.